http.c: Ensure valid object on freelocale(3)

According to POSIX.1-2008, the behaviour is undefined if freelocale(3)
is called with an invalid object. [1]

[1]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/freelocale.html

1 files changed, 3 insertions, 1 deletions

diff --git a/http.c b/http.c
index 014dcc6..261dcc0 100644
--- a/http.c
+++ b/http.c
@@ -2780,7 +2780,9 @@ static int append_expire(struct dynstr *const d, const struct tm *const exp)
     ret = 0;
 
 end:
-    freelocale(l);
+    if (l != (locale_t)0)
+        freelocale(l);
+
     return ret;
 }